Mower-knife sharpener.



T. J. ALLISTON. MOWERKIHFi E SHARPENEEh APPLICATION FILED sE-PT. 1.191a.

Patented Nov; 2?, 1917..

THOMAS J. ALLIS'ION, OF MARION, ILLINOIS.

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Application filed September 1, 1916.

To all whom it may concern:

Be it known that I, THOMAS J. ALLISTON, a citizen of the United States,residing at Marion, in the county of Williamson and State of Illinois,have invented certain new and useful Improvements in Mower-KnifeSharpeners; and I do hereby declare the following to be a full, clear,and exact description of the invention, such as will enable othersskilled in the art to which it appertains to make and use the same.

This invention relates to improvements in that type of mower knifesharpener in which the sharpening device is pivotally mounted within theknife guard, and adapted to be swung on the pivot by the teeth of thecut tingblade during the passage of the blade through the guard and toengage'the teeth so as to effect sharpening of the same, and

- an object of the-invention is to mount the sharpening device withinthe guard in such a novel manner that the same can have both verticalbodily movement and vertical swinging movement, so that the entirecutting edge of the blade will be engaged by the sharpening device asthe blade passes through the guard.

Another object of the invention is the provision of a novel type ofknife guard having a receiving recess therein underlying the sharpeningdevice for collecting dirt and such matter that will. be liberated fromthe teeth of the knife during the sharpening operation, the walls of therecess having discharge openings therein to admit of the escape of thecollected matter from the recess so that the collected matter will notinterfere with the sharpening operation.

Other objects will appear and be better understood from that embodimentof my invention of which the following is a specification, referencebeing had to the accompanying drawings forming a part thereof, in which:

Figure 1 is a top plan view of the guard with the improved sharpeningdevice associated therewith,

Fig. 2 is a side view thereof,

Fig. 3 is a longitudinal 'section taken through the guard, showing theposition assumed by the sharpening device during the sharpeningoperation,

Fig. 4 is a section taken on the line H of Fig. 2, and

Fig. 5 is a detail perspective view of the.

sharpening device detached from the guard.

Specification of Letters Patent.

Patented Nov. 27, 191?.

Serial No. 118,059.

Referring to the drawings in detail, the numeral 1 designates the guardhaving its rear end provided with an attaching flange 2, adapted to besecured to the portion 3 of a mowing machine by means of a bolt 1 and anut 5. y The forward end of the guard tapers, as shown at 6, and formedon the upper side of the guard, adjacent the tapered end, is a pair ofspaced apertured ears 7. A U-shaped frame 8 is disposed above the upperside of the guard 1 and has the ends of the sides thereof formedintegral with the ears 7. A plate 10 is secured to the upper side of theguard 1 and underlies the Ll-shaped frame 8, and has its opposite longitudinal edges beveled, as shown at 11, to provide. the cutting edgeswhich cooperate with the cutting edges of the teeth 12 carried by acutter blade 13, which latter reciprocates through the space between theframe 8 and the plate 10.

The sharpening device is located within the Ushaped frame 8 and movablethere in and consists of a sharpening element 14:, formed preferably ofemery and having a very fine operating surface, the said sharpeningelement being carried by a frame 15, the rear end of which is providedwith an extension 16, which is received between the ears 7 on the guardand the sides of the frame 8, and is provided with a diagonallyextending elongated slot 17 that receives a pivot pin 18, which extendsthrough the opposed ears 7, as shown more particularly in Fig. 3 of thedrawings. The operating surface of the sharpening element 14 is rounded,as shown at 19, and extends throughout the length of the element 14. Theplate 10 is provided with a central recess 20, the walls of which arebeveled, as shown in Fig. 4E, and the said recess 20 is adapted toreceive the lower grinding or sharpening surface of the sharpeningelement 1 1 after the sharp ened tooth has passed from the guard, andbefore the next adjacent tooth is moved into the guard. This admits ofthe sharpening element 14 assuming a position where it will effectivelyengage the tooth of the cutter when inserted w thin the guard. Aninverted substantially U-shaped spring 21 has one end secured to theupper side of the tapered end of the guard 1, and its opposite endslidably received by aguide slot 22 formed on the upper side of theframe 15, which carries the grinding or sharpening element 1 1. When oneof the cutting edges of a tooth is moved into the guard the rear endthereof will be the first portion to be presented beneath the sharpeningelement, owing to the triangular shape of the tooth, and will effectvertical pivotal movement of the cutting element carrying frame 15.During the travel of the tooth through the guard and the gradualpresentation of the outer end of thecutting edge beneath the sharpeningelement, the sharpening element-carrying frame 15 will be given verticalbodily movement, the slot 17 which receives the pivot 18 admitting ofthis vertical bodily movement of the frame 15 being effected. By virtueof the fact that the sharpening element-carrying frame has bodilymovement during the passage of the cutting edge of the tooththerebeneath, and also by reason of the fact that the free end of thespring rests on the upper side of the frame 15, the pressure-of thesharpening element 1 f against the cutting edge of the tooth will beconstant. The guard 1 is provided, at a point below the re cess 20 inthe plate 10, with a chamber 23 which is adapted to receive the materialscraped or liberated from the cutting tooth during the sharpeningoperation. The side walls of the chamber 23 are provided with opposedelongated slots or openings 24, which will admit of the matter collectedin the chamber 23 being discharged therefrom, so that danger of thecollected matter filling the chamber 23 and preventing the cuttingelement 14 being lowered to the position whereby the sharpening surfacewill be prevented from being received by the recess 20 in the plate 10,will be overcome.

Having thus described my invention what I claim as new, is:

1. In a mower knife sharpener, the com bination with a knife guard,apertured ears fixed on the upper side of the guard, a frame overlyingthe'guard, a sharpening element carried by the frame, an extensioncarried by the frame and located between the ears on the guard andhaving an elongated slot therein, and a pivot pin extendingthrough theears and the slot'in the extension.

2. In a mower knife sharpener, the combination with a knife guard, of asharpening element carrying frame, and means for connecting the'frame tothe-guardfor tilting and vertical bodily movement; on the guard, and aspring having one end connected'to the guard and its opposite end freeand overlying and resting on the upper side of the sharpening elementcarrying frame. i V

3. In a mower kDlfBfShELI'PGIlGI, the combination with a knifeguard, ofa spring having one end secured to the guard, a sharpening elementcarrying "frame having a slot therein forreceiving'the other end of thespring, and meansffor connecting the sharpening element carrying frameto the guard for tilting and vertical bodily movement on the guard.

at. In combination, 'amower knife guard,

a knife sharpening element mounted onthe guard, the'said guard havingacollecting chamber therein underlying the knife sharpening element,and'two of the opposed side walls of thechamber having-dischargeopenings therein, forthe purpose specified.

In testimony whereof I aflix my signature in presence of two witnesses.f THQMAS J. ALLISTON. Witnesses:

J. C; KETTNE J. "W. BURNETT.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of'lfatents,

Washington, D 0..

